1. Field
The present disclosure relates to single focal length lens systems, interchangeable lens apparatuses, and camera systems.
2. Description of the Related Art
In recent years, interchangeable-lens type digital camera systems (also referred to simply as “camera systems”, hereinafter) have been spreading rapidly. Such camera systems realize: taking of high-sensitive and high-quality images; high-speed focusing and high-speed image processing after image taking; easy replacement of an interchangeable lens apparatus in accordance with a desired scene; and the like.
As lens systems to be used in interchangeable lens apparatuses, compact lens systems having high optical performance have been desired. For example, various kinds of lens systems having a three-unit configuration have been proposed.
Japanese Laid-Open Patent Publications Nos. 2012-242472 and 2013-037080 each disclose a lens system having a three-unit configuration of positive, negative, and positive, in which an aperture diaphragm is placed in a first lens unit, and a second lens unit performs focusing.